LONDON – The U.K. debut of Sam & Cat on Monday night gave Nickelodeon here its best series launch ratings ever, continuing the success of the hit show in international markets.

The Viacom network's iCarly and Victorious spin-off launched in Britain in the 6 p.m. Monday time slot and drew an average of 240,100 kids and 293,700 overall viewers. The figures include live and immediate DVR viewing. That resulted in "the best launch" on Nickelodeon U.K. ever, according to the network.

The performance was up 228 percent from the network's average for that time slot among kids aged 4-15.

Nickelodeon U.K. was the top kids channel and number two across all channels in Britain -- behind Channel 4, which aired The Simpsons -- in the 6 p.m.-6:30 p.m. Monday time slot, according to network data. Sam & Cat also ranked as the top-rated show on Monday across all U.K. kids networks.

As of Tuesday afternoon, 276,200 kids and 331,800 total viewers had watched the first episode of Sam & Cat.

The show, which launched in the U.S. in June, stars former iCarly actress Jennette McCurdy and Victorious star Ariana Grande. The girls become roommates and start a babysitting service.

The series has been a ratings hit for Nickelodeon in various countries since its launch. Its U.S. debut reached 4.2 million total viewers, making it the network's biggest live-action launch in three years.

The German premiere in late September saw Sam & Cat become the top-rated show on the country's Nickelodeon channel in its launch week, beating the channel's slot average of the previous weeks.

The late September launch in the Netherlands also made Nickelodeon the country's top kids channel during the premiere and beat the local network's slot average.

In Poland, Nickelodeon became the number one kids and overall channel during the premiere. Compared to the slot average from the previous six weeks, the show was up 58 percent.